You have the Peper trojan, which requires special treatment to put it out of your misery!Please download and run this uninstaller.

Click on the peperfix link, and download the program. Then go off line, and run the program. It will remove the files, leaving one orphaned entry to be cleaned up with Hijack this.

Have Hijack This fix all of the following by placing a check in the appropriate boxes and hitting fix checked. Make sure all browser and all Windows Explorer windows are closed before fixing.R3 - Default URLSearchHook is missing